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as yet unknown to men, but which will be discovered to be wonderful and fantastic beyond anything of a like nature now familiar. In other places cavities exist between shelves of rock that lie one above the other—monstrous openings caused by the erosive action of rivers now lost, but that have flowed during unnumbered ages past; great parallel valleys and gigantic chambers, one over the other, remaining to tell the story of these former torrents. Occasionally the weight of a portion of the disintegrating rock above becomes too great for its tensile strength and the material crumbles and falls, producing caverns sometimes reaching so near to the earth's surface, as to cause sinks in its crust. These sinks, when first formed, as a rule, present clear rock fractures, and immediately after their formation there is usually a water-way beneath. In the course of time soil collects on their sides, they become cone-shaped hollows from the down-slidings of earth, and then vegetation appears on the living soil; trees grow within them, and in many places the sloping sides of great earth bowls of this nature are, after untold years, covered with the virgin forest; magnificent timber trees growing on soil that has been stratified over and upon decayed monarchs of the forest whose remains, imbedded in the earth, speak of the ages that have passed since the convulsions that made the depressions which, notwithstanding the accumulated debris, are still a hundred feet or more in depth. If the drain or exit at the vortex of one of these sinks becomes clogged, which often occurs, the entire cavity fills with water, and a pond results. Again, a slight orifice reaching far beneath the earth's surface may permit the soil to be gradually washed into a subterranean creek, and thus are formed great bowls, like funnels sunk in the earth—Kentucky punch-bowls.

"Take the country about us, especially towards the Mammoth Cave, and for miles beyond, the landscape in certain localities is pitted with this description of sinks, some recent, others very old. Many are small, but deep; others are large and shallow. Ponds often of great depth, curiously enough overflowing and giving rise to a creek, are to be found on a ridge, telling of underground supply springs, not outlets, beneath. Chains of such sinks, like a row of huge funnels, often appear; the soil between them is slowly washed through their exit into the river,